The UPSILON PHI SIGMA 1935 - Honor and Excellence Service Fraternity and Sorority was originally organized by Seven (7) U.P. students from the different Colleges of the University of the Philippines(UP) in the year 1935. It was formally organized by its Seven Founders on February 14, 1935, and purposely on the day of the hearts to meaningfully emphasize its concepts of love and peace. This foundation day is a very important day in the lives of all the true-blooded UPSILONIANS.
Since then it is celebrated annually with much fun fare and appropriate activities with renewals of fraternal vows of commitment and dedications to the UPS1935 ideals.

On May 14, 1935, the 7 Founders and its original members crafted a simple yet a very comprehensive Constitution and By-Laws document encompassing the fraternal principles, concepts of love and peace, and doctrines of self and organizational disciplines, under the vision of Honor, Service and Excellence in all its activities. The Fraternity also promulgates since then its adherence to the ideals of this Republic and its respect to the duly-constituted authorities.

Established as an independent and unique organization in the Philippines, many well-meaning students from various schools in Metro Manila clamored to be admitted as bonafide members of the newly-organized UPSILON PHI SIGMA 1935 which has finally decided at that time to include in its roster of membership females or ladies of character to constitute the Sorority membership. From that time on,
UPSILON PHI SIGMA 1935 Fraternity and Sorority has expanded its membership and leadership with hundreds of strong Chapters organized not only in Metro Manila but also in the different parts of Luzon, Visayas and Mindanao. At present it has already Chapters and Alumni groups in other countries like Australia, New Zealand, U.S.A., Canada, Guam, Germany, Taiwan, Saudi Arabia and community Chapters in Kota Kinabalu (Malaysia) and other parts of Asia.

The UPSILON PHI SIGMA 1935 Inter-University and Collegiate Honor and Excellence Service Fraternity and Sorority is committed for the lifetime development of its individual members. It inculcates in its proud members the lasting brotherhood and sisterhood in the spirit of Unity, Peace and Prosperity for All! It also develops in its members the qualities of good leadership and self-confidence among other important values, with focus on organizational loyalty.

The UPSILON PHI SIGMA 1935 Fraternity and Sorority therefore maintains its basic role as the fraternal symbol of Honor and Excellence, not only on its proactive leadership, but also importantly to its guided and committed membership nationwide.